“More than 300 divers – including open water instructors — have died in caves just like this one. Prevent your death. Go no further.”

Now, I can’t speak for anyone but myself, but when I was a fledgling open water diver, if faced with a sign that shared that little snippet of information with me, I am pretty sure that I would have turned around and gotten the heck out of dodge. Big signs with that wording and an image of the Grim Reaper are placed at the entrance to most caves in Florida as well as other spots in the Bahamas, Mexico and so on. But sadly, many divers, divers who have no business being in any overhead environment and especially a cave, choose to ignore them.

The question is why?

If you take a look through the standards for SDI’s open-water programs – from beginner to open-water instructor trainer – there are some very specific recommendations to stay away from “overhead environments.” For the record, an overhead environment is ANY spot from which a direct ascent to the surface is not possible. And to further clarify, a direct ascent means that if a diver were to fill a lift bag, DSMB, or balloon at depth and release it, it should make it to the surface without touching rock, wreck, coral or anything else. If that lift bag, DSMB, or balloon DOES touch anything at all, the diver should be trained and equipped, to be there.

OK, more definitions. It’s fair to say that the foundation of most of the skills, techniques and gear associated with technical diving have their beginnings in cave diving. Cave diving is – to many – where sport diving stops and technical diving begins. Certainly, courses in cave diving from TDI are considered “Fully technical” and for good reason.

Since the inception of structured cave diving education, the progress from being an experienced open-water diver to a full cave diver has followed a similar pathway regardless of the certifying agency or location of the program being offered.

It begins with a cavern course. This program is designed to introduce basic skills such as how to swim without kicking up a huge cloud of silt; how to use a reel and deploy a line in water without getting tied up like a Christmas present; how to communicate with your buddy so there’s no ambiguity; and how to manage gas volume so that you and your mate have something to breathe for the duration of the dive even if something goes totally pear-shaped and one of you loses all his gas.

The next step in cave diver training is an Intro-to-Cave class. This builds on the fundamental skills presented in the cavern class and introduces more intensive equipment management drills. Graduates from this level of training can venture into the cave, but still have to function within certain limits, such as staying in the main passageways and making no jumps to side passages.

And finally is a full-cave class which essentially gives a diver a “licence to learn,” inside the cave proper and its off-shoots and side tunnels. But even then, there are limits and several other steps in both experience and training before this diver has “free-run” of the cave.

NONE of the skills required to help keep a diver safe in a cave or cavern are taught in a recreational open-water class… including an instructor class… and the equipment used by sport divers the world over has no place in a cave.

Caves can be beautiful but that beauty can become extremely ugly in a couple of heartbeats. Here are some things that have happened to untrained divers who almost died in a cavern or cave but somehow managed to find their way out.

“We only intended to swim in a little way, but there were lots of passages and we got turned around…”
“The water was really clear but my buddy crashed into the bottom and I lost sight of him and the exit. I think he is still in there…”
“We had a light between us but it went out. It was really dark and I kept swimming into the walls…
“I swum in a little way and then my octo started to freeflow…”
“We followed a line and it just stopped and then I got tangled in it…”
“I panicked when I turned and could not see the exit.”

Let’s look again at some definitions. The definition of a cavern, and the limit of a cavern dive, is that the primary light is sunlight. Cavern divers must still use and carry lights (several of them), but at all times, both divers must be able to see the exit of the cavern. And for the record, the Grim Reaper sign mentioned in the first paragraph is usually placed at the edge of the so-called cavern-zone… the transition point from cavern to cave.

Now, just in case you are thinking to yourself right now: “Well, I guess it’s OK to go and take a peek inside a cavern because the sign telling me to go no further is there and NOT at the entrance to the cavern itself” let’s consider a couple of things including the benefits and reasons behind the skills taught cavern divers.

Remember the first rule of scuba diving: Never hold your breath? Well, the first rule of technical diving delivers more or less the same message: “Always have something to breathe!” That way, you never HAVE to hold your breath and break the first rule of scuba diving.” That makes sense doesn’t it?

Many of the several hundred divers who have perished in caves have actually died in the cavern zone: right there within sight of the exit. How, you might ask, could that happen? After all, it’s just a cavern, nothing challenging about that! Well, as surprising as it may seem, they ran out of something to breathe because they could not see daylight. They had flutter-kicked their way a few metres into the cavern and in doing so had totally silted things out so badly that they were suddenly in a black-out. They found themselves lost! Then, with their breathing rate elevated because of stress… and then panic… they had used up their air supply in minutes while searching for the way out. In their confusion, some had actually swum further into the cave.

Occasionally, the poor sap who ends up dead may have been told that caverns and caves are safe, and believed it. There may even have been an open-water instructor telling them that it’s OK to follow them into a cavern or cave. Well, the truth is that is in NOT OK and dive leaders who take untrained divers into an overhead are breaking standards… pure and simple.

There are no grey areas when it comes to this overhead stuff. Going in there without the right kit and training is seriously tempting fate, and there are so many other ways to enjoy yourself with scuba. Please, please, do not go into an overhead until you get training in overhead diving and get yourself some serious kit and gain the experience to use it properly.

Steve Lewis
TDI instructor trainer #6

Contact SDI TDI and ERDI
If you would like more information, please contact our World Headquarters or your Regional Office.